A field trial on competitive displacement between Aedes polynesiensis and A. albopictus is underway on the island of Taiaro in French Polynesia. An inspection trip to determine the progress of this experiment is to be made in January or February, 1974. In the laboratory, cross breeding experiments are underway with all possible combinations of the following members of the Aedes scutellaris group: A. pseudoscutellaris from Fiji; 3 strains of A. polynesiensis (Samoa, Tahiti, Taiaro); A. malayensis from Bangkok; A. sp. from Tafahi (Tonga Islands); A. sp. from Niuafo'oa (Tonga Islands) and A. cooki from Niue. In addition to observations on genetic compatibility, observations will be made on the inheritance of autogeny (the species from Tonga and A. cooki are autogenous); and on the morphological characters of the parent and hybrid populations.